In China, environmental issues caused by construction and operation of highway catch more and more attention, and thus environmental impact assessment of highway has become an important part of feasibility study. According to the Specifications for Environmental Impact Assessment of Highways in the People's Republic of China, this paper proposes an integrated model for Environmental Impact Assessment (EIA) of highway. The model has two main characteristics. Firstly, the whole highway is divided into several sections, and then weight of each section is distributed by its importance. Secondly, a novel method is presented to standardize the second-class quantitative indexes. The proposed model is scientific, rational, objective, comprehensive and well operable. Its performance is satisfied in practice.